28JW-74H (serv.man5). Important servicing notes - Sharp TV Service Manual (repair manual)

28jw-74h (serv.man5) service manual
28JW-74H (serv.man5)
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Service Manual
TV / CTR / Important servicing notes

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Only qualified service personnel are allowed to carry out maintenance and repair of this receiver.
Servicing of High Voltage System and CRT
It is important that the static charge is removed from the high voltage system when carrying out work on the
receiver. This can be achieved by connecting a 10K resistor (with a suitably insulated lead) from the CRT
cavity connector to the CRT ground tag. This must be carried out with the AC supply disconnected from the
Note the following:
The CRT in this receiver employs Integral Implosion Protection.
• If the CRT has to  be changed  it  MUST  be  replaced  with  the  correct  type for continued safe  working.
• DO NOT lift the CRT by its neck.
• When handing the CRT, ensure that shatterproof goggles are worn.
• Ensure that the CRT is discharge before handling.
This receiver is designed to keep any x-ray emission to an absolute minimum. Some fault conditions  and
servicing procedures may produce potentially hazardous x-ray radiation levels. This is a problem when in
close proximity to the receiver for long  periods of time. To reduce any risks associated with this, please
observe the following precautions:
1. When undertaking any servicing on this chassis, DO NOT increase the EHT  to more than 32.0 KV, (at a
instantaneous beam current of 1500
2. Ensure that during normal operation the EHT does not exceed 29.5KV±1.5KV (at a beam current of
µA). This level has been preset in the factory. Always check that this level has not been exceeded
after carrying out any repair on the receiver.
3. DO NOT replace the CRT with any other type than that specified in the parts listing as this may cause
excessive x-ray radiation.
Before returning the receiver to the customer
In addition to the above checks, the following should also be carried out before  returning the receiver  to the
1. Inspect all the leads to ensure that they are dressed correctly and that they are not obstructed or pinched
by any other parts.
2. Ensure that all protective devices are in good condition. These will include nonmetallic control knobs,
insulating fish papers, cabinets backs, compartment covers or shields, mechanical insulators, etc.

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Here you can read online and download Sharp 28JW-74H (serv.man5) Service Manual in PDF. 28JW-74H (serv.man5) service manual will guide through the process and help you recover, restore, fix, disassemble and repair Sharp 28JW-74H (serv.man5) CTR. Information contained in service manuals typically includes schematics / circuit diagrams, wiring diagrams, block diagrams, printed wiring boards, exploded views, parts list, disassembly / assembly, pcb.